Superelastic/Shape Memory Tissue Stabilizers and Surgical Instruments

ABSTRACT

A surgical instrument is used for temporary use in a medical procedure in a mammalian body. The surgical instrument is configured to be changed between two shapes upon application of one or both of heating and cooling. The instrument includes a first member, a second member having a surface configured to contact tissue, and a means to apply heating or cooling to one or both of the first member and the second member to change the shape between a first shape and a second shape. A surgical instrument also may be configured to be changed between two shapes upon removal of a constraining force. The surgical instrument includes a first member, a second member having a surface configured to contact tissue, and a constraining means to apply a constraining force to one or both of the first member and the second member to cause one or both of the first member and the second member to be in a first constrained shape. The surgical instruments may be used in minimally invasive valve surgery.

RELATED APPLICATIONS

This application is a continuation of and claims the benefit of priorityunder Title 35, United States Code, §120 from U.S. patent applicationSer. No. 10/235,486, filed Sep. 6, 2002, which claims priority under 21USC § 119(e)(1) of prior U.S. provisional patent application 60/317,182,filed Sep. 6, 2001 and titled Superelastic Tissue Stabilizer, both ofwhich are incorporated herein in their entirety by reference.

TECHNICAL FIELD

The technical field of the invention relates to localized tissuestabilization for stabilizing tissue during, for example, a beatingheart or off-pump coronary artery bypass grafting (CABG) procedure.

BACKGROUND

It is well-known that diseases of the cardiovascular system affectmillions of people each year and are a leading cause of death in theUnited States and throughout the world. One form of cardiovasculardisease is ischemia, in which there is a reduction in the blood supplyleading to the heart. This reduction is caused by atherosclerosis or anyother condition that creates a restriction in blood flow at a criticalpoint in the cardiovascular system that supplies blood to the heart. Forsome patients, the blockage or restriction in the blood flow can besurgically treated by coronary artery bypass grafting (CABG), commonlyreferred to as a “coronary bypass” operation. In this procedure, thesurgeon removes a portion of a vein or artery from another part of thebody and uses it as a graft to bypass the obstruction and restorecirculation to the heart.

The surgeon uses the graft to bypass the obstruction by attaching oneend to the ascending aorta and attaching the other end to a coronaryartery, distal to the obstruction. The procedure of making theseattachments is known as an anastomosis. This can be performed with theheart stopped and the patient put on cardiopulmonary bypass or, during abeating-heart CABG procedure, while the heart muscle is continuing tocontract and pump blood. However, in the latter case, the anastomosis isdifficult to perform because the heart is moving and pumping blood atthe same time that the surgeon is suturing the graft in place.

Importantly, the sutures must be carefully placed so that the graft isfirmly attached and does not leak when blood flow through the graft isestablished. During a beating-heart CABG, it is important that theprocedure be performed rapidly because the blood flow through the targetcoronary artery may be interrupted or reduced during the procedure inorder to create the anastomosis without excessive blood loss. Moreover,if the beating heart CABG procedure is performed partially or completelyin a minimally invasive manner, the working space and visual access maybe limited because the surgeon may be working through a small incisionin the chest or may be viewing the procedure on a video monitor if thesite of the surgery is viewed via a surgical scope.

SUMMARY

In one general aspect, a surgical instrument is used for temporary usein a medical procedure in a mammalian body. The surgical instrument isconfigured to be changed between two shapes upon application of one orboth of heating and cooling The instrument includes a first member, asecond member having a surface configured to contact tissue, and a meansto apply heating or cooling to one or both of the first member and thesecond member to change the shape between a first shape and a secondshape.

Embodiments of the surgical instrument may include one or more of thefollowing features. For example, application of cooling causes one orboth of the first member and the second member to become malleable.Application of heating causes one or both of the first member and thesecond member to change shape. The application of heating may includeone or both of supplying a heated fluid to one or both of the firstmember and the second member and receiving in one or both of the firstmember and the second member the heat generated by the mammalian body.The application of cooling may causes the surface configured to contacttissue to adhere to the tissue.

The surgical instrument may further include a source to apply vacuum tothe surgical instrument, the second member including at least oneopening passing through the surface configured to contact tissue and theapplication of vacuum to the surgical instrument adheres the surfaceconfigured to contact tissue to the tissue. The surgical instrument alsomay further include one or more channels in one or both of the firstmember and the second member. The channels may be designed for one ormore of application of vacuum, application of heating, application ofcooling, application of a therapeutic agent, application of a secondsurgical instrument, and application of shaping mandrils. The shapingmandrils impart a shape in, or rigidify, one or both of the first memberand the second member.

The second member may include one or more feet, each of the feetincluding a surface configured to contact tissue. The surface that isconfigured to contact the tissue may include a removable component forremovably attaching to each of the feet.

The first member may be connected to the second member by a pivotaljoint that includes a finned surface that pivotally mates with a curvedsurface. The surgical instrument may further include a handle extendingfrom the first member, the handle including a nonthreaded thumb slide tolock the finned surface against the curved surface to fix the positionof the first member relative to the second member.

The surgical instrument may further include a delivery tube, a thirdmember and a fourth member having a surface configured to contacttissue. The second member and the fourth member include feet, each ofthe feet including the surface configured to contact tissue, and thefeet being separately controllable by controlling the movement of thefirst member and the second member.

The surgical instrument may be one or both of a tissue retractor and atissue stabilizer. The surgical instrument may be made from a shapememory material, including being made from a shape memory metal such asNitinol.

In another general aspect, a surgical instrument for temporary use in amedical procedure in a mammalian body to be placed in contact withtissue is configured to be changed between two shapes upon removal of aconstraining force. The surgical instrument includes a first member, asecond member having a surface configured to contact tissue, and aconstraining means to apply a constraining force to one or both of thefirst member and the second member to cause one or both of the firstmember and the second member to be in a first constrained shape.

Embodiments of the surgical instrument may include one or more of thefollowing features. For example, the constraining means may beconfigured to be moved relative to the first member and the secondmember to remove the constraining force from one or both of the firstmember and the second member to allow one or both of the first memberand the second member to return to an unconstrained shape. One or bothof the first member and the second member may be fabricated from asuperelastic material, including being made from a superelastic metalsuch as Nitinol. The surgical instrument may be one or both of a tissueretractor and a tissue stabilizer.

The surgical instrument may further include a source to apply vacuum tothe surgical instrument, the second member including at least oneopening passing through the surface configured to contact tissue and theapplication of vacuum to the surgical instrument adheres the surfaceconfigured to contact tissue to the tissue. The surgical instrument alsomay further include one or more channels in one or both of the firstmember and the second member. The channels may be designed for one ormore of application of vacuum, application of heating, application ofcooling, application of a therapeutic agent, application of a secondsurgical instrument, and application of shaping mandrils. The shapingmandrils impart a shape in, or rigidify, one or both of the first memberand the second member.

The second member may include one or more feet, each of the feetincluding a surface configured to contact tissue. The surface that isconfigured to contact the tissue may include a removable component forremovably attaching to each of the feet.

The first member may be connected to the second member by a pivotaljoint that includes a finned surface that pivotally mates with a curvedsurface. The surgical instrument may further include a handle extendingfrom the first member, the handle including a nonthreaded thumb slide tolock the finned surface against the curved surface to fix the positionof the first member relative to the second member.

The surgical instrument may further include a delivery tube, a thirdmember and a fourth member having a surface configured to contacttissue. The second member and the fourth member include feet, each ofthe feet including the surface configured to contact tissue, and thefeet being separately controllable by controlling the movement of thefirst member and the second member.

In another general aspect, a surgical instrument is temporarily used ina medical procedure in a mammalian body. The method of temporarily usingthe surgical instrument in the medical procedure in the mammalian bodyincludes providing a surgical instrument fabricated from a shape memorymaterial and being configured to be changed between two shapes in themammalian body upon application of one or both of heating and cooling.The surgical instrument includes a delivery device, a first member, asecond member having a surface configured to contact tissue, and a meansto apply heating or cooling to one or both of the first member and thesecond member to change the shape between a first shape and a secondshape. The method further includes applying cooling to one or both ofthe first member and the second member and placing one or both of thefirst member and the second member into the delivery device in a firstshape; advancing the delivery device in the mammalian body; advancingthe first member and the second member in the delivery device such thatat least one of the first member and the second member extend out of thedelivery device into the mammalian body; applying heating to one or bothof the first member and the second member to change the shape of one orboth of the first member and the second member from the first shape to asecond shape; using the second member to contact tissue; and removingthe surgical instrument from the mammalian body.

Embodiments of the method may further include one or more of thefollowing features. For example, the surgical instrument may be used inone or more of minimally invasive valve surgery, stabilization oftissue, retracting tissue, delivery of vacuum to tissue, application ofheating to tissue, application of cooling to tissue, application of atherapeutic agent, application of a second surgical instrument, andapplication of shaping mandrils through channels in the first memberand/or second member, whereby the mandrils impart a shape in, orrigidify, one or both of the first member and the second member.

The application of cooling may cause one or both of the first member andthe second member to become malleable. Application of heating may causeone or both of the first member and the second member to change shape.The application of heating may include one or both of supplying a heatedfluid to one or both of the first member and the second member andreceiving in one or both of the first member and the second member theheat generated by the mammalian body. The application of cooling maycauses the surface configured to contact tissue to adhere to the tissue.

In the method, the surgical instrument may further include a source toapply vacuum to the surgical instrument, the second member including atleast one opening passing through the surface configured to contacttissue and the application of vacuum to the surgical instrument adheresthe surface configured to contact tissue to the tissue. The surgicalinstrument also may further include one or more channels in one or bothof the first member and the second member. The channels may be designedfor one or more of application of vacuum, application of heating,application of cooling, application of a therapeutic agent, applicationof a second surgical instrument, and application of shaping mandrils.The shaping mandrils impart a shape in, or rigidify, one or both of thefirst member and the second member.

The second member may include one or more feet, each of the feetincluding a surface configured to contact tissue. The surface that isconfigured to contact the tissue may include a removable component forremovably attaching to each of the feet.

The first member may be connected to the second member by a pivotaljoint that includes a finned surface that pivotally mates with a curvedsurface. The surgical instrument may further include a handle extendingfrom the first member, the handle including a nonthreaded thumb slide tolock the finned surface against the curved surface to fix the positionof the first member relative to the second member. The surgeon may movethe thumb slide to fix the position of the first member relative to thesecond member.

The surgical instrument may further include a delivery tube, a thirdmember and a fourth member having a surface configured to contacttissue. The second member and the fourth member include feet, each ofthe feet including the surface configured to contact tissue, and thefeet being separately controllable by controlling the movement of thefirst member and the second member.

The surgical instrument may be one or both of a tissue retractor and atissue stabilizer. The surgical instrument may be made from a shapememory metal such as Nitinol.

In another general aspect, an apparatus for stabilizing tissue includesa handle segment comprising a first material, a stabilizing segmentcomprising a second material, and an arm segment connecting the handlesegment to the stabilizing segment and comprising a third material. Atleast one of the first material, the second material, and the thirdmaterial comprise a superelastic material.

In another general aspect, an apparatus for stabilizing tissue includesa handle segment, a stabilizing segment, and an arm segment connectingthe handle segment to the stabilizing segment. The stabilizer is formedto have a first shape, coolable to have a second shape, and heatable toregain the first shape.

In another general aspect, an apparatus for stabilizing tissue includesa handle segment, a stabilizing segment including at least one lumen,and an arm segment including at least one lumen. The arm segmentconnects the handle segment to the stabilizing segment. The stabilizingsegment lumen is connected to the arm segment lumen and is configured toreceived a mandril.

In another general aspect, the inventors have developed a localizedtissue stabilizer for use during beating heart surgery, specifically tostabilize the area around the site of the distal coronary anastomosisduring a coronary artery bypass graft (CABG) procedure that is minimallyinvasive, port access, robotically assisted or other type of surgicalprocedure. The stabilization device may also be used in endoscopic andlaparoscopic procedures. The stabilizer, or specific sections of thestabilizer, may be made from a superelastic/shape memory metal alloy(e.g., Nitinol) that allows a section or sections of the stabilizer tobe flexed into a reduced profile for insertion through the chest wall.Once through the wall, the stabilizer returns to the desired shape oncethe constraining forces have been removed. Additionally oralternatively, reinforcing members may be used to rigidify the flexedareas. The stabilizer can also be similarly flexed during withdrawalfrom the chest cavity. The stabilizer generally utilizes compression,static or active vacuum, combination, or other methods to remain incontact with the heart surface. The tissue stabilizer, as described, orwith simple modifications, has additional utility as a heart positioner(e.g., to manipulate the heart position to access side or posteriorvessels), as well as a tissue retractor (e.g., for use during minimalaccess valve surgery).

A localized tissue stabilizer for use during beating heart surgery,specifically to stabilize the area around the site of the distalcoronary anastomosis during a coronary artery bypass graft (CABG)minimally invasive, port access, robotically assisted or other types ofsurgical procedures. The stabilization device may also be used inendoscopic and laparoscopic procedures. The stabilizer, or specificsections of the stabilizer, is made from a superelastic/shape memorymetal alloy, such as nitinol, that allows the distal section of thestabilizer to be deformed into a reduced cross section profile forinsertion through the chest wall. Once through the wall, the stabilizerreturns to the desired shape once the constraining forces have beenremoved or in the case of shape memory materials, heat causes thestabilizer to return to its annealed configuration. The stabilizer canalso be similarly deformed during withdrawal from the chest cavity. Thestabilizer utilizes compression, static or active vacuum, cryo,adhesive, protrusions, or combination to remain in contact with theheart or tissue surface.

The stabilizer and stabilizer systems described herein provideconsiderable advantages. For example, the stabilizer can have a shaft orarm segment with a minimized cross-section for increased surgical fieldvisibility for the surgeon. The stabilizer can be deformable andcollapsible for easy insertion and withdrawal through a minimal accessor narrow opening. The stabilizer and related devices can be configuredwith insertable mandrils to modify the shape and/or rigidity of thestabilizer, before, during, or after the device's insertion into a bodycavity, such as the thoracic cavity and can be removed to facilitatewithdrawal. The stabilizer is designed to be compatible (i.e.,mountable) with most commonly available supporting brackets, arms,rails, etc. and cardiothoracic retractors. The stabilizer is designed toprovide tissue immobilization or stabilization using a simple vacuumand/or a mechanical means, such as compression. The vacuum can belocally controlled or remotely controlled and incorporated to passthrough the inside of the shaft or arm segment, or on the outside of theshaft or arm segment. The stabilizer can be provided with multiple,interchangeable feet and/or contacting surfaces, including single ormultiple malleable or spring elements. The stabilizer can beadvantageously designed for increased access and visualization of theanastomotic or surgical field or site by using a low profile arm segmentand feet and/or contacting surfaces as well as by passing the vacuum orfluid lines, tubes or conduits within the device itself. The stabilizeradvantageously can have independent feet and/or contacting surfacerotation which provides benefits during procedures of the epicardialsurface and other convex tissue or organ surfaces. The stabilizer may beadvantageously fabricated completely or partially from a shape memory orsuperelastic material such that the device deflects the impact of aforce or blow, such as the beating of the heart. This transfers force tothe device so that it flexes and there is less trauma to the heart,providing atraumatic stabilization. Alternatively, if the shaft isbowed, increased compressive force against the tissue surface isadvantageously provided. The device also can include a cooling featureto cool the superelastic or shape memory material, which advantageouslyprovides easy insertion and withdrawal of the device through a confinedor narrow opening.

The details of one or more embodiments of the stabilizer are set forthin the accompanying drawings and the description below. Other featuresand advantages of the stabilizer will be apparent from the description,the drawings, and the claims.

DESCRIPTION OF THE FIGURES

FIG. 1 is a perspective view of a tissue stabilizing apparatus.

FIG. 2 is a perspective view of the tissue stabilizing apparatus of FIG.1 being used to stabilize tissue.

FIG. 3 is a perspective view of a second implementation of a tissuestabilizing apparatus.

FIG. 4 is a perspective view of the tissue stabilizing apparatus of FIG.3 with a retracted foot section 110.

FIGS. 5 and 6 are perspective views of the tissue stabilizing apparatusof FIG. 3 with the feet sections in the process of expanding from theretracted configuration of FIG. 4 to the configuration of FIG. 3.

FIGS. 7-10 are various implementation of stabilizer segment of thetissue stabilizing apparatus of FIG. 1.

FIGS. 11 and 12 are side and perspective views, respectively, of ahandle configuration for use particularly with the tissue stabilizingapparatus of FIG. 10.

FIGS. 13 and 14 are cross-sectional side views of a semicircular armsegment of a tissue stabilizing apparatus in an unrestrained and arestrained configuration, respectively.

FIGS. 15 and 16 are cross-sectional side views of a cross-shaped armsegment of a tissue stabilizing apparatus in an unrestrained and arestrained configuration, respectively.

FIGS. 17 and 18 are perspective views of stabilizers configured with aninternal and external, respectively, spraying apparatus terminating inthe feet.

FIGS. 19 and 20 are perspective views of the stabilizers of FIGS. 17 and18 having a spraying apparatus terminating in the transition between thestabilizing segment and the arm segment.

FIGS. 21-24 are perspective views of stabilizers having one or moreinternal channels configured to receive one or more mandrils.

FIG. 25 is a perspective view of a stabilizer in a scissoredconfiguration.

FIGS. 26 and 27 are perspective views of a stabilizer system usingseparate stabilizers within a tubular member.

FIG. 28 is a perspective plan view of a stabilizer with an activetemperature control system.

FIG. 29 is a perspective side view of a temperature control tube for usewith the stabilizer of FIG. 28.

FIG. 30 is a flow chart depicting the fabrication of an exemplarystabilizer.

FIGS. 31A-S are bottom views of the feet and/or contacting surfacesshowing various textured surfaces suitable for improved contact with atissue surface.

FIGS. 32A-H are profile views of the geometry of feet and/or contactingsurfaces.

FIGS. 33A and 33B are sectional bottom and side views of a suctionapparatus for the feet and/or contacting surfaces of a stabilizer.

FIGS. 34A and 34B are sectional bottom and side views of a suctionapparatus for the feet and/or contacting surfaces of a stabilizer.

FIGS. 35A and 35B are sectional bottom and side views of a suctionapparatus for the feet and/or contacting surfaces of a stabilizer.

FIG. 36 is a bottom view of stabilizing segment having protrusions orbarbs extending from the stabilizing segment.

FIG. 37 is a perspective view of a stabilizer having vacuum capability.

FIG. 38 is a bottom view of a stabilizer segment of the stabilizer ofFIG. 37.

FIG. 39 is an enlarged view of the attachment of the stabilizer segmentto the stabilizer.

FIG. 40 is an enlarged view of the handle of the stabilizer of FIG. 37.

FIG. 41 is an enlarged view of stabilizer segment provided as a separateattachment to the stabilizer of FIG. 37.

FIG. 42 is a perspective view of a stabilizer having internally placedvacuum lines.

FIG. 43 is an enlarged side view of the attachment of the stabilizersegment to the stabilizer of FIG. 42.

FIG. 44 is a bottom view of the stabilizer segment of the stabilizer ofFIG. 42.

FIG. 45 is a perspective side view of a stabilizer having an indexed andpivotable stabilizer segment.

FIGS. 46 and 47 are enlarged top and perspective side views of theindexed and pivotable stabilizer segment of FIG. 45.

FIGS. 48 and 49 are perspective side views of a stabilizer having a pairof independent stabilizers.

FIG. 50 is a perspective bottom view of the stabilizer of FIGS. 48 and49.

FIG. 51 is a side view of the independent stabilizers of FIGS. 48 and 49withdrawn into a delivery tube.

FIG. 52 is a perspective side view of a retractable stabilizer having anopen stabilizer segment.

FIG. 53 is a bottom view of the open stabilizer segment of FIG. 52.

FIG. 54 is a side view of the retractable stabilizer of FIG. 52 havingthe open stabilizer segment withdrawn into a delivery tube.

FIG. 55 is a perspective side view of a stabilizer having a clamp pivotmechanism between the stabilizer segment and the shaft.

FIG. 56 is a cross-section side view of the clamp pivot mechanism.

FIG. 57 is a front view of the stabilizer segment showing ridges.

FIG. 58 is a top view of a lower clamp half of the clamp pivot mechanismshowing ridges.

FIG. 59 is a cross-sectional side view of a fin-type pivot mechanism.

FIG. 60 is a bottom view of the fins.

FIG. 61 is a side view of fins using vertical spikes.

FIG. 62 is a side view of a shape memory/superelastic surgicalinstrument.

FIG. 63 is a side view of the shape memory/superelastic surgicalinstrument extended from a delivery tube.

FIG. 64 is a side view of the shape memory/superelastic surgicalinstrument extended from the delivery tube and configured in anunconstrained shape.

FIGS. 65 and 66 are side views of a shape memory/superelastic surgicaldevice including a J-shaped surgical instrument.

FIGS. 67 and 68 are side view of a shape memory/superelastic surgicaldevice including a hockey stick shaped surgical instrument.

FIGS. 69, 70, and 71 are side views showing the stabilizer or retractorbeing used as a carrier to pass a therapeutic or diagnostic devicethrough a lumen in the stabilizer or retractor into an opening, groove,slot, or hole in a stabilizing segment, feet, and/or contractingsurface.

DETAILED DESCRIPTION

Referring to FIG. 1, a stabilizer 100 for stabilizing tissue includes ahandle segment 105, a stabilizing segment 110, and an arm segment 115.The arm segment 115 connects the handle segment 105 to the stabilizingsegment 110. The apparatus is configured to be used by a surgeon whopositions and presses the stabilizing segment 110 against a tissuesurface to stabilize the tissue surface for a surgical procedure, andmounts the arm segment to a retractor or an arm or rail that is attachedto the retractor or similar apparatus. For example, the apparatus 100can be used by a cardiac surgeon to stabilize a section of a beatingheart to perform a bypass of a coronary artery, by an orthopedic surgeonto stabilize the position of tissue during arthroscopic surgery, or asurgeon during any minimally invasive surgeon of the abdominal region.In any of these procedures, or any similar procedure, the surgeon isable to insert the stabilizer 100 into a confined space within apatient, stabilize tissue, perform the intended surgical procedure, andremove the apparatus without the necessity of opening the surgicalregion anymore then is necessary. Optionally, the surgeon can insert ordeliver the stabilizer 100 through a confined delivery device, such as around or oval tube. The arm segment of the stabilizer is connected to aconventional retractor arm or rail, as is well known in the art, so thatit can be moved into the desired position, and then is secured in thatposition using a friction, matching geometry, or other connectingdevice. Such surgical arms or retractors are available from manycompanies, including Genesee BioMedical (Denver, Colo.) and ChaseMedical (Richardson, Tex.).

In general, the stabilizer 100 and other stabilizers described hereinare made, in part or completely, of a superelastic or shape memorymaterial, such at a nickel titanium alloy (e.g., nitinol). Thestabilizer can include the characteristic of the ability to be formed toa first shape, cooled to form a malleable apparatus having a secondshape, and heated passively or actively to regain the first shape.Moreover, the material can be resilient so that it can absorb a force byflexing without being permanently deformed. The details of forming thestabilizer are described in greater detail below but, in general, ashape memory or superelastic material is cut and then annealed in ashaping fixture that is placed in a heat source, such as an oven or saltpot, and then cooled in the shaped position to impart the shape to thematerial.

It is important to understand basic terminology when describing metalswith elastic, superelastic, or shape memory behavior. In general,elasticity is the ability of a metal, under a bending load, for example,to deflect (i.e., strain) and not take a permanent “set” when the load(i.e., stress) is removed. Common elastic metals can strain to about twopercent before they set. Superelastic metals are unique in that they canwithstand up to approximately ten percent strain before taking a set,although this application is not limited to superelastic metals thatwithstand up to approximately ten percent strain. A superelasticstabilizer will work as well with a material that can be strained morethan ten percent or less than ten percent. The ability to withstandstrain is attributed to a “stress-induced” phase change within the metalto allow it to withstand such dramatic levels of strain. This is adesirable feature in collapsible tissue stabilizing/tissue retractingdevices. Depending on the composition of the metal, the temperature thatprovides such a phase change can vary. Further, if the metal is “set” atone temperature, and then the temperature is changed, the metal canreturn to its “unset” shape. Then, upon returning to the previous “set”temperature, the shape changes back. This is a “shape-memory” effect dueto the change in temperature changing the phase within the metal. Thefollowing explanation of superelasticity and shape memory propertiesdescribes these different metal behaviors, along with the compositionsof various superelastic and shape memory alloys.

Elasticity. When a metal is loaded (i.e., stressed) and undergoes, forexample, bending, it may deflect (i.e., strain) in a “springy” fashionand tend to return to its original shape when the load is removed, or itmay tend to “set” and stay in a bent condition. This ability to returnto the original shape is a measure of the elasticity or “resilience” ofthe metal. This ability for a metal to be resilient is desirable wherethe ability to deflect, but not deform (i.e., set) is important tomaintain an applied force. Thus, elasticity is a highly desirablefeature for a flexible, collapsible tissue stabilizer, tissue retractor,and/or heart positioner.

Plasticity. If, under a bending load, the metal takes a set, it is saidto have plastically (versus elastically) deformed. This is because theimposed stress produced by the bending load has exceeded the “yieldstrength” (i.e., stress) of the metal. Technically, this level of stressthat produces a set, is referred to as the “elastic limit”, but isapproximately the same value as the yield strength. If the applied loadincreases past the yield strength of the metal, it produces moreplasticity and can eventually break. The higher the yield strength ofthe metal, the more elastic it is. “Good” elastic metals can accommodateup to about two percent strain prior to taking a set. However, this isnot the only factor governing “elasticity”.

Modulus. Another factor that determines the ability of a metal todeflect to a given, desired amount, but not take a set, is the “elasticModulus”, or often called the modulus of elasticity. The “modulus” ofthe metal is an inherent property. Steels, for example, have arelatively high modulus (30 msi) while the more flexible aluminum has alower modulus of about 10 msi. The modulus for titanium alloys isgenerally between 12 and 15 msi.

Resilience. Resilience is the overall measure of elasticity or“spring-back ability” of a metal. The ratio of the yield strengthdivided by the modulus of the metal is the resilience. Although it isone thing for a metal to be resilient, it must also have sufficientstrength for the intended service conditions.

Superelastic metals. As discussed above, when a metal is loaded, eachincrement of load (stress) produces a given increment of deflection(strain) within the metal. The metal remains elastic if the applied loadis below the yield stress. However, there is a unique class of metalalloys that behave in an even more elastic manner. These are thesuperelastic metals, where, for a given applied stress (load) increment,the strain in the metal can reach 5 or 6 percent or more without takinga set. In this type of metals, the overall strain required to produce aset can reach an impressive 10 percent. This phenomenon is related to aphase change within the metal that is induced by the applied stress.This “stress-induced” phase change also can be used to set the metal atone temperature and return the metal to another shape at anothertemperature. This is known as a “shape-memory” effect, which isdiscussed below.

The most common superelastic metal is an alloy comprised ofapproximately equal parts of nickel (Ni) and titanium (Ti), and soldunder the trade name of “Nitinol” or “NiTi.” By slightly varying theratios of the nickel and titanium in Nitinol, the stability of theinternal phases in the metal can be changed. Basically, there are twophases: an “austenite” phase and a lower-temperature, “martensite”phase. When the metal is in an austenitic phase condition and isstressed, a stress-induced martensite forms, resulting in thesuper-elasticity. This is reversible, and the original shape returnsupon release of the applied stress.

In general, the nickel to titanium ratio in the Nitinol is selected sothat the stress-induced martensite forms at the temperature of use, suchas ambient temperatures for the devices that are used in ambientconditions. The specific composition can be selected to result in thedesired temperature for the formation of the martensite phase (Ms) andthe lower temperature (Mf) at which this transformation finishes. Boththe Ms and Mf temperatures are below the temperature at which theaustenite phase is stable (As and Af). The performance of a tissuestabilizing, tissue positioning, and/or tissue retracting device can befurther enhanced with the use of superelastic materials such as Nitinol,that will return to their intended original shape when released withinthe chest cavity.

Shape Memory Metals. By manipulating the composition of Nitinol, avariety of stress-induced superelastic properties can result. Theproperties can be tailored to occur over a desired, predeterminedservice temperature range. This allows the metal to behave in a“shape-memory” or “shape recovery” fashion. In this regard, the metal is“set” to a predetermined, desired shape at one temperature when in amartensitic condition, but which returns to the original shape when thetemperature is returned to the austenitic temperature.

The shape memory phenomena occurs from a reversible crystalline phasechange between austenite and the lower-temperature martensite. Inaddition to this transformation occurring from an induced stress asdescribed previously, it can, of course, also change with temperaturevariations. This transformation is reversible, but the temperatures atwhich these phase changes start and finish differ depending on whetherit is heated or cooled. This difference is referred to as a hysteresiscycle. This cycle is characterized by the four temperatures mentionedpreviously, As, Af, Ms, and Mf. Upon heating from a lower-temperaturemartensite, the transformation to austenite begins at the As, and isfully austenite at Af. Upon cooling, austenite begins to transform backto martensite at the Ms temperature, and becomes fully martensitic atthe Mf temperature. Again, the specific composition of the alloy can beused to provide a desired combination of these four transformationtemperatures.

In the malleable martensitic state, the alloy can be easily deformed(set). Then upon heating back to the austenitic temperature, the alloyfreely recovers back to its original shape. Then, if cooled back to themartensitic state, the deformed shape is re-formed. The typical sequenceof utilizing this shape memory property is to set the shape of, forexample, a tissue stabilizer, while in the higher-temperature austeniticstate. Then, when cooled, deform the martensite material, and then heatto recover the original shape.

These materials also can be used to form very tight bends. With thebackground given above, it can be seen that if a device or componentconstructed from Nitinol requires an exceptionally tight bend that wouldnormally exceed the elastic limit of the material and thus permanentlydeform it, a bend can be placed in the device and the device annealed torelieve bending stresses within the device. Following this first bend,the device can be bent further to produce an even sharper bend, and thenre-annealed to alleviate the stress from this additional bending. Thisprocess can be repeated to attain the desired, sharp bend or radius thatwould otherwise permanently deform the device if the bend were attemptedin a single bending event. The process for recovery from the position ofthe most recent bend is then performed as described above.

This shape memory ability is very advantageous for devices including,tissue stabilizers, tissue retractors, heart positioners, etc. Thesedevices can be deformed and maintained in their martensitic state (e.g.,can use a cooling agent if Mf is below room temperature) until they areintroduced and released in the body. Then, a warm, sterile solution,short electrical activation, or other suitable means (free recovery ifAf is less than 37° C.) can be applied to trigger the recovery of thepredetermined shape. In some implementations, the material remainsaustenitic after cooling to body temperature. This is achieved bychoosing an alloy composition with a hysteresis such that Ms is neverreached upon cooling to normal operating conditions (i.e., Ms below bodytemperature). High-temperature martensite shape memory alloys are alsoan alternative composition for these implementations.

Although Nitinol is the most popular of the superelastic metals, thereare other alloys that exhibit superelastic or shape-memory behavior.These include the following:

Copper-40 at % Zinc

Copper-14 wt % Aluminum-4 wt % Nickel

Iron-32 wt % Manganese-6 wt % Silicon

Gold-5 to 50 at % Cadmium

Nickel-36 to 38 at % Aluminum

Iron-25 at % Platinum

Titanium-40 at % Nickel-10 at % Copper

Manganese-5 to 35 at % Copper

Titanium-49 to 51 at % Nickel (Nitinol)

In summary, there are various ways of characterizing elasticity, but auseful criteria is the ability of the metal to return to its initial,pre-loaded shape. Some metals can only deflect a few percent and remainelastic while others, such as superelastic Nitinol, can deflect up toapproximately ten percent. Nitinol offers other advantages because italso is biocompatible and corrosion resistant. This unique combinationof properties allows a device made of Nitinol, such as a tissuestabilizer, tissue retractor and/or heart positioner, to be deflectedduring insertion through the chest wall and return to the form of itsintended service (i.e., annealed) shape.

Referring again to FIG. 1, the handle segment is configured for asurgeon to easily grasp and position the stabilizer during a surgicalprocedure. For example, the handle segment 100 may include an innermaterial, such as a metal or a plastic, and an outer material, such as ametal or a plastic. For example, the inner material can be a plasticthat has been injection molded or machined to have an ergonomic shape.The outer material can be a low durometer plastic against which thesurgeon's glove is unlikely to slip or slide, and which can be coated,over molded, or injection molded around the inner material with orwithout texture to provide additional resistance to slippage.

The arm segment 115 is configured to have a low profile and, forexample, be passed through a tube. The arm segment can be made of anybiocompatible material, such as a metal or a plastic. A metal armsegment can be integrally formed with a metal handle segment or can beseparately attached to a metal or a plastic handle segment. Similarly, aplastic arm segment can be integrally formed with a plastic handlesegment or can be separately attached to a plastic or a metal handlesegment. The arm segment 115 can be shaped to have a minimal profile andyet retain a certain amount of rigidity.

The stabilizing segment 110 can be formed integrally with the armsegment 115, as illustrated in FIG. 1, or formed separately and thenattached to the arm segment. In general, the stabilizing segment 110includes one foot, two feet, or more than two feet 120. The feet 120 areplaced in contact with the tissue to be stabilized or otherwiseimmobilized. As described in more detail below, a lower surface of thefeet can be coated with a contacting section 125. As described in moredetail below, the contacting section can be configured to provide anatraumatic surface to contact tissue; a non-slip surface to reduce orprevent movement of the feet 120 when in contact with the tissuesurface; a member to apply vacuum, a mist or stream of a fluid to atissue surface; and/or a continuous or intermittent inflated surfaceagainst the tissue. The interface between the stabilizing segment 110and the arm segment 115 optionally includes a gradual transition segment130 and a weakened segment 135. The transition segment 130 is configuredsuch that the stabilizer 100 can be withdrawn through a tube or aconfining member (not shown) with a confined volume such the transitionsegment will cause the feet 120 of a superelastic material to be foldedtogether by gradually accepting the frictional pressure caused by theinteraction of the stabilizer as it is pulled through the tube. Theoptional weakened segment 135 can be in the form of a removed section ofmaterial placed such that the weakened segment will cause bending orcollapsing at its location. As illustrated in FIG. 1, the weakenedsegment is in the form of a slot cut into or formed with the stabilizer100. The weakened segment 135 causes the feet 120 to collapse in towardseach other when under friction or an inward pressure. The weakenedsegment can be formed anywhere on the stabilizer in which bending orcollapsing is desired.

The surgeon uses the stabilizer 100 to stabilize or otherwise immobilizea portion of tissue. For example, as illustrated in FIG. 2, the surgeoncan use the stabilizer to stabilize cardiac tissue 140 (i.e., a heart)during beating heart coronary artery bypass grafting surgery. In thisprocedure, the surgeon grasps the handle 105 and positions thestabilizing section 110 against the cardiac tissue 140 such that thepair of feet 120 and/or contacting section 125 are placed on oppositesides of the coronary artery. Although the weakened segment 135 is notillustrated in FIG. 2, it, of course, may be incorporated within thisimplementation of the stabilizer.

Referring to FIG. 3, in a second embodiment of a stabilizer apparatus, astabilizer 150 includes the handle 105, the stabilizer section 110, thearm section 115, and the individual feet 120. The stabilizer 150optionally includes the contacting sections 125. The feet 120 are formedwith an elevated segment 155 that elevates the transition between thefeet 120 and the arm segment 115. The elevated segment 155 providesconsiderable advantages in procedures such as coronary artery bypasssurgery, as illustrated in FIG. 2, because the stabilizer section 110can be placed against cardiac tissue adjacent to a coronary arterywithout compressing the vessel and restricting the blood flow of thecoronary artery. The elevated segment 155 includes bent segments 160with tapered bends to provide atraumatic surfaces that prevent damagingthe tissue against which the stabilizer is applied.

Although the stabilizer 150 may be introduced by a surgeon into a bodycavity through a conventional open field, it also may be inserted into abody cavity through a narrow opening, such as a narrow incision, inbetween the ribs, a tube, and/or a confining member. To easeintroduction through a narrow opening, the stabilizing segment 110 canbe retracted and/or folded together in a collapsed configuration, asillustrated in FIGS. 4 and 5. In particular, FIG. 4 illustrates the feet120 completely bent back and generally parallel with the arm segment115. In this configuration, the combination of the arm segment 115 andthe feet 120 have a very narrow profile such that the surgeon canintroduce the device through a very narrow opening. Moreover, the feet120 can be bent back or forward and generally curved across its widthalong the length to have a minimal cross-sectional profile. In FIG. 5,the feet 120 are shown part way through the process of expanding awayfrom the arm segment 115. FIG. 6 illustrates the feet 120 being furtheralong in the process of expanding away from the arm segment, althoughnot completely yet expanded to its final configuration, as illustratedin FIG. 3.

FIGS. 7-10 illustrate additional implementation of the stabilizersegment 110. For example, FIG. 7 illustrates a stabilizer 175 with theelevated segment 155 being configured to provide extra clearance fromthe tissue, which is especially advantageous in coronary artery bypasssurgery to prevent occlusion of a coronary artery. In thisimplementation, the contacting surfaces 125 are overmolded or adhered tothe lower surface of the feet 120 using adhesive, mechanicalinterference fit, a combination of these, or other means, although theycan be formed completely around the outer circumference and surface ofthe feet 120. The contacting surfaces 125 may be made of, for example,silicone, polyurethane, combination of these, or other materials, orother biocompatible plastic available in low durometers and capable ofcreating a slip-resistant surface. As described in additional detailbelow, the outer or lower surface of the contacting surfaces 125 can beformed with a surface configuration or texture to further enhance theslip-resistance of the contacting surfaces. The feet 120 of FIG. 7generally are formed integrally with the arm segment 115, although thecan be separately formed and later attached to the arm segment.

FIG. 8 illustrates a stabilizer 185 having feet 120 that are overmoldedwith contacting surfaces 125. The contacting surfaces also may beseparately formed and then slipped over the feet 120. For example, thefeet 120 may have a first outer diameter segment 190 and a second outerdiameter segment 195, with the first outer diameter segment having agreater diameter than that of the second diameter segment, and thecontacting surfaces 125 can be in the form of a tube having an innerdiameter that is very close to the diameter of the second diametersegment. In this manner the contacting surface can be slid over thesecond diameter segment 195 and held in place by an optional frictionfit or with the use of an adhesive, combination or other.

In addition, the feet 120 can be separately formed and attached tomounting surfaces 200 on the arm segment 115. The feet can be attachedusing welding, soldering, adhering with an adhesive, a press fitinterface, a threaded attachment, or any other known attachment meanssuitable for application to a medical device. In the configuration ofFIG. 8, as well as the other configurations shown herein, the feet 120can be configured for insertion into a narrow opening by retractingbackwardly one foot 120 and extending forwardly the other foot 120.

Referring to FIG. 9, a stabilizer 210 is formed with the stabilizersegment 110 being integral with the arm segment 115. In thisimplementation, a round, oval, flat, or otherwise shaped shaft is cutalong its length, generally along its central longitudinal axis. The cutcan be formed using any known conventional cutting method, including alaser, a cutting saw, chemical etching, electron discharge machining(EDM), stamping, photolithographic techniques, water jet, and/or anycombination of these methods. The opposing sides of the cut then areforced outwardly to form an opening 213. The cut can be made through thedistal end 215 of the shaft or can stop short of the distal end, asillustrated in FIG. 9. The stabilizer 210 then is formed by shaping theshaft and attaching the handle segment 105. Optionally, the distal end215 can be elevated to prevent occlusion of a coronary artery if thestabilizer 210 is to be used in coronary artery bypass procedures. In aderivative implementation, multiple incisions may be made along thelength of the shaft. For example, one central incision may be made alongthe length and extend through the distal end 215 and two incisions maybe made in the thus formed opposing segments of the shaft, although notcompletely through their distal ends. Those two incisions then may beforced apart to form a pair of stabilizing segments, each of which beingsimilar to the stabilizing segment illustrated in FIG. 9.

Referring to FIG. 10, a stabilizer 220 is formed from a single piece offlat material, such as a metal, using any of the known conventionalmethods of cutting, shaping, bending, forging, and otherwise formingmetal. For example, using a flat metal sheet, the stabilizer 210 can becut by a laser, a cutting saw, chemical etching, electron dischargemachining (EDM), stamping, photolithographic techniques, water jet,and/or any combination of these methods. As described below, the cutpiece then can be processed to form the three-dimensional shapeillustrated in FIG. 9, and a handle attached. Of course, the handle canbe formed integrally with the stabilizer 210 from the flat metal sheetand have an ergonomic configuration, as illustrated in FIGS. 11 and 12.The handle segment 105 can be configured to include a first portion 225and a generally parallel second portion 230. The first portion 225 iscurved for easy gripping by the surgeon and provides region to provide asnug fit of the fingers against the second portion 230. In thisconfiguration, the handle segment 105 can be fabricated from asuperelastic material, such as Nitinol, or other material.

Moreover, referring to FIGS. 13-16, the arm segment 115 can befabricated from a superelastic material, such as a superelastic shapememory metal or plastic, have a semicircular profile (FIG. 13) whenunrestrained, and have a reduced diameter, low profile shape whenrestrained (FIG. 14). In another implementation, the arm segment canhave a cross-shaped profile (FIG. 15) when unrestrained, and have areduced diameter low profile, rounded shape when restrained (FIG. 16),for example, during delivery into a narrow opening into a body region.

Referring to FIGS. 17 and 18, the stabilizing apparatus can beconfigured as a stabilizer 250 that includes an internal misting orspraying capability or attachment 255 (FIG. 17) or as a stabilizer 260that includes an external misting or spraying capability or attachment265 (FIG. 18). The misting can be partially or fully atomized and be adiffuse, broad or focused mist, combination of these, or adjustable. Theinternal spraying attachment 255 includes a tube 270, such as a polymertube, that passes through channels in the handle segment 105, the armsegment 115, and terminating within or on top of the outer surface ofone or both of the feet 120. The distal end of the spraying attachment265 can include one or more openings 275 through which a fluid, such assaline, or a gas, such as CO₂, or other fluid or gas can be continuouslyor intermittently sprayed, for example, to maintain a clear surgicalfield during the procedure. The tube 270 can be connected to a syringeto manually inject the fluid, to a pump to automatically dispense thefluid, or a container of fluid to that uses gravity to dispense thefluid, gas or other to the tissue. Alternatively, as illustrated in FIG.18, the tube 270 can be attached, using known conventional attachmentmeans, such as by using a Luer fitting to the outside of the handlesegment 105, the arm segment 115, and/or the feet 120. Attaching thetube 270 to the outside of the stabilizer is believed to reduce the costof producing the stabilizer.

Referring to FIGS. 19 and 20, the stabilizers 250 and 260 can beconfigured such that the tubes 270 terminate in one or more openings 280at the transition between the stabilizing segment 110 and the armsegment 115. A fluid or gas as described above then can be dispensedthrough the opening(s) 280 onto the surgical field.

Although the stabilizer 250 is illustrated as having the tube insertedthrough the handle segment and arm segment, the stabilizer can beconfigured to have an internal channel that terminates in openings inthe feet or at the transition between the stabilizer segment and the armsegment. The tube 270 can be threadably or otherwise attached to thehandle and fluid dispensed into the channel and out of the openings. Forexample, the tube 270 can be attached using a Luer fitting or othercommon fitting or connector.

FIGS. 21-24 illustrate stabilizers having channels configured to receiveshaping or reinforcing mandrils. In general, after the stabilizer isinserted into a confined body region, such as the thoracic cavity, themandrils are inserted into the channels to modify the shape of thestabilizer and/or increase the rigidity of the stabilizer. For example,referring specifically to FIG. 21, the arm segment 115 of a stabilizer300 includes a channel 305 that passes from approximately the handlesegment to the transition region between the stabilizing segment 110 andthe arm segment. A mandril (not shown) can be configured to fit looselyor tightly within the channel 305 and when it is inserted into thechannel 305 the stabilizer's shape can conform to the shape of themandril. Additionally, the mandril provides increased rigidity to thestabilizer 300. To vary the rigidity of the stabilizer 300, mandrils ofdifferent rigidities, created by varying the material or diameter of themandril, can be inserted into the channel 305. As shown in thestabilizer 310 illustrated in FIG. 22, the channel 305 can extend fromthe handle segment 105 to the end of the arm segment 115. The mandrilsalso may be connected to the arm, rail, or retractor for ensuring thatthe mandrils are kept in position within the stabilizer.

The mandrils may be made from superelastic/shape memory materials, suchas metal alloys (e.g., nitinol); polymers; composites; spring alloyssuch as Inconel™, and Elgiloy™; malleable material, such as stainlesssteel, polymers, or other known materials. The geometriccharacteristics, such as diameter, cross-sectional profile, thickness orany combination of these can be varied to affect the rigidity,flexibility of other physical characteristics of the mandril, and thusthe stabilizer. For example, the cross-sectional profile can be shapedlike an X, T, Y, concentric, eccentric, and/or tubular. The X, T, and Yshapes allow a fluid to be passed around the mandril. The mandrils maybe mounted in position in the stabilizer using a variety of mountingand/or attachment devices, as are well-known in the art, including anannular friction seal, a locking geometry, threaded valve seal connectorsuch as hemostatic valve, a clip that mounts to the handle and themandril, and/or a combination of these. For example, a fitting with arotatable end cap may be rotated to compress a circular valve material,such as silicone, around the mandril to lock the mandril in position.

Referring specifically to FIG. 23, the stabilizer 300 can be configuredto include multiple channels 305 that pass from the handle segment 105,through the arm segment 115, and terminate in the feet 120. In thisconfiguration, a mandril can be inserted completely or partially intoeach channel 305 as desired to provide a desired configuration orrigidity.

As illustrated in FIG. 24, the stabilizer 310 can be configured toinclude the single channel 305 that passes through the arm segment 115and then splits into multiple channels 315. Rigidity and shape isimparted in the stabilizer 310 by a mandril that includes a distal endhaving a pair of shaped extensions that fit within the channels 315.

Referring to FIG. 25, a stabilizer 325 can be configured as a pair ofscissored feet 120 that are connected through a hinge or screw 330between the pair of arm segments 115. By fabricating the stabilizer 325from a shape memory/superelastic material, the stabilizer can beinserted in a first, narrow profile through a narrow opening and thenallowed to expand to a second, wider profile in which the feet 120 aresubstantially or partially perpendicular to the arm segments 115 so thatthe surgeon can manipulate and press the feet against a tissue surface.Although the stabilizer 325 is illustrated as including feet 120 forstabilizing or otherwise immobilizing tissue, the feet 120 can bereplaced with angled blades for cutting, angled tissue graspers forgrasping and holding tissue, or any other surgical tool that benefitsfrom the ability to be inserted in a first, narrow profile and thenallowed to expand to a second, wider and/or larger profile.

Referring to FIGS. 26 and 27, the stabilizer apparatus can beimplemented as a stabilizer system 350 that includes a pair ofindependent stabilizers 355 that are passed through a tubular member360. Each stabilizer 355 includes the handle 105, the arm segment 115,and the stabilizing segment 110. In the configuration of FIGS. 26 and27, the stabilizing segment includes a single foot 120. The surgeon caninsert the system 350 into a narrow opening by first pulling thestabilizers back such that the feet 120 are completely withdrawn intothe tubular member 360. With the tubular member positioned within thebody cavity, the surgeon advances the stabilizers 355, separately ortogether, until the feet 120 are extended. The surgeon can independentlymanipulate the handles 105 to select a position of the feet 120 thatallows the surgeon to stabilize the tissue. Although FIGS. 26 and 27show simplified implementations of the feet 110, the feet can beimplemented in a more complex configuration with the curves and bendsillustrated in the feet described herein.

The center-to-center distance between the feet can be manipulated bymoving the parallel arm segments 115 apart, creating a “V” shape.Additionally, a snap on spacer component may be positioned in betweenthe two arm segments, at a proximal or middle position, or slid downtowards the distal end of the arm segment, resulting in the same spaceseparation at the feet. Also, a thumb wheel type device (e.g., similarto that on a drafter's compass) may be used to manipulate thecenter-to-center width of the feet.

Referring to FIG. 28, a stabilizer 375 can be configured to be cooledand/or heated as necessary for affecting the rigidity of the stabilizer,inserting and removing the stabilizer from a narrow opening, or toprovide therapeutic benefit to the tissue against which the stabilizeris placed or in its general vicinity. Moreover, heating and cooling canbe used to provide a preventative effect or utility, such as duringcooling of tissue during ischemic periods of CABG procedures. Thestabilizer 375 includes the handle segment 105, the arm segment 115, andstabilizing segment 110. The stabilizer also includes a channel 380 thatpasses through the handle segment 105 and the arm segment 115, andoptionally into the stabilizing segment 110. The channel 380 can splitinto a pair of channels 385 that extend into the feet 120. Heated orcooled fluid can be directed into the channels 380 and 385 to heatand/or cool the stabilizer. The fluid can be provided from a tube 387that is connected to an opening 390 in the handle segment 105, althoughthe opening can be placed elsewhere in the stabilizer, such as, forexample, in the arm segment. The tube 387 is connected on its other endto, for example, a pump 393, a bag of fluid, reservoir, or other sourceof providing heated or cooled fluid.

The tube also can be configured to have a dual lumen with both lumensopening into the handle opening 390. The other end of the tube canterminate to a pair of connectors that are each in communication withone of the lumens. In this configuration, a source of cooled or heatedfluid can be inserted through one lumen into the channel 380 andwithdrawn through the other lumen by a suction, a vacuum source, activepumping of the fluid, or combination of these methods or other similarmethods. In this manner, the temperature of the fluid provided to thestabilizer 375 can be quickly increased or decreased. In thisconfiguration, the stabilizer can include temperature sensors (e.g.,thermocouples, thermistors) or probes to measure localized temperatureto provide temperature feedback information for the physician. Thisinformation can be used as part of a feedback loop in temperaturesensing and controlling to control the heating or cooling of the tissuesurface or stabilizer component to maintain or control the temperatureof the tissue and/or stabilizer, for example, based on a set point.

Referring to FIG. 29, in another implementation of a method to heat orcool the stabilizer 375, a dual lumen, temperature control tube 400 canbe inserted into the opening 390 and passed into the channel 380. Thedual lumen tube 400 includes a pair of connectors 405 that are each incommunication with one of the lumens 410. One of the connectors 405 canbe connected to a fluid source and the other connector can be connectedto a fluid withdrawal apparatus, such as a pumping, vacuum, or suctionsource, an opening, or merely gravity. A closure insert 415 can be usedto hold the position of the tube 400 within the channel 380 and providea fluid tight seal. For example, the insert 415 can be threadablyinserted into the opening 390 such that fluid will not pass out theopening 390 except through one of the lumens 410 of the tube. The insertmay include a central opening that includes a gasket and the tube passesthrough the gasket in a fluid-tight manner. Alternatively, a fittingwith a rotatable end cap may be rotated to compress a circular valvematerial, such as silicone, around the component to lock the componentin position in the stabilizer. The tube also may include side holes 420along its length through which fluid can be inserted and/or removed. Thedistal end of the tube also can be opened, closed, or one of theopenings opened and the other closed.

Using a controlled source of heated or cooled fluid, the surgeon canminimize the amount of time that the stabilizing segment is rigidly incontact with the tissue. For example, shortly before the surgeon is tostabilize the tissue he can inject heated fluid to cause the stabilizingsegment 110 and/or the arm segment 115 to become rigid. Similarly, ifthe surgeon believes that the rigidity is excessive for the particularsurgical condition, he can specify a reduction in the temperature of thefluid being supplied to the stabilizer. After training, it isanticipated that the surgeon will be able to mentally connect the fluidtemperature with the rigidity of the stabilizer and be able to quicklyspecify a temperature to provide the needed rigidity or flexibility. Thesurgeon also can specify a fluid temperature based on knowledge orbelief that temperature will have a therapeutic effect on the tissue.

The stabilizers described above can be made using a number of materialsand methods. For example, the shaft or arm segment material can be madefrom a superelastic and/or shape memory alloy, such as nitinol (a nickeltitanium alloy). These materials are available in many configurations,and from suppliers, such as NDC (Fremont, Calif.); Memry Corporation(Bethel, Conn.); and Shape Memory Applications, Inc. (San Jose, Calif.).Other materials that can be used include spring stainless steel (e.g.,17-7), other spring metal alloys such as Elgiloy™ or Inconel™ andsuperelastic polymers.

Referring to FIG. 30, which details an exemplary process for forming asuperelastic/shape memory stabilizer, the shaft or arm segment 115 canbe processed into the desired shape and size using a number ofwell-known methods, such as electronic discharge machining (EDM), lasercutting, photolithography and chemical etching, grinding, cutting,sintering, casting, molding, stamping, and/or any combination of thesemethods. First, the shaft material, and other optional shapememory/superelastic component, would be formed to the desired length,for example, by any cutting method (step 450). The shaft and othercomponent then would be placed or positioned in an annealing and formingfixture to impart a desired shape in the material (step 455). The armsegment can be made from a sheet, a bar, a single or multiple tube orrod. The shaft may be a tube with a slot at the distal end that isannealed into the desired footpad configuration. The shaft may be ofconsistent width or thickness, or varied to modify therigidity/flexibility, or other characteristic of the stabilizer.

The arm segment can be made from one or more rods, tubes, bands, coils,or other. They also may be partially or completely coated (or overmolded) with any biologically acceptable material, such as a lowfriction polymer. As illustrated above, the arm segment may have one ormore lumens that, for example, pass from the proximal end handle to thedistal region of the stabilizer, for suction, CO₂ or saline misting, orfor other purposes. The lumens may be on the inside, outside or both ofthe shaft, and could be constructed from a metal, metal alloy orpolymer, or combination. The stabilizer may be a composite made fromstainless steel (or other material) with the transition area between thearm segment and the feet or stabilizing segment being partially orcompletely made from superelastic/shape memory material or spring metalalloy, essentially becoming a deflectable hinge or elbow that may or maynot require reinforcement, for example, using a reinforcing mandril orsleeve once inside the thoracic cavity or other body cavity.

The annealing fixture may have one or more surfaces around which theshaft would be positioned into a constrained arrangement, which closelyresembles the final deployed configuration. The fixture also may beadjustable to make slight modifications in the shape due to, forexample, changes necessitated by the surgeon or by the annealingprocess. The annealing fixture may be made from a metallic material thatis able to withstand the annealing temperatures, and may have single ormultiple components or sections. To anneal multiple arm segmentssimultaneously, the various components or sections of the fixture may beheld together with clamps, screws, rods, or combinations of these orother components.

The fixture then would be subjected to heat, for example, by beingplaced in an oven or a salt pot (step 460). To anneal a superelastic orshape memory alloy, the alloy should be subjected to a temperature ofapproximately 300-800° Celsius for approximately two to thirty minutes.For example, a temperature of approximately 500° Celsius has been usedsuccessfully to fabricate a tissue stabilizer. The temperature and thetime spent annealing are dependent upon factors, such as the thicknessof the material (e.g., the stabilizer and the annealing fixture), thematerial, and the shape to be imparted, etc. Following annealing, thematerial is removed from the heat and quickly quenched in cold water(step 465). Steps 455-465 may be repeated as necessary, includingadjustment of the fixture to make small, increment changes in the radiusof curvature, angle, or bend between each annealing cycle to preventover-stressing of the material when securing it to the fixture. Afterthe shape is imparted in the material, it may be bead blasted,electropolished, or other suitable method that cleans and smoothes thesurface and remove any burrs from the surfaces (step 470).

The handle segment may be, for example, injection molded polycarbonateor another polymer material. The handle could be over-molded directlyonto the stabilizer shaft, or molded separately and then bonded to theshaft with adhesives or other (step 475). The handle segment also mayincorporate a connection means for vacuum, CO₂ or saline misting,reinforcing or shaping mandrils, or other purpose, as described above.

The feet 120 and contacting surfaces or feet pad 125 optionally then aremounted to the arm segment 115 (step 480). Of course, the feet 120 canbe integrally formed with the arm segment. If not integrally formed, thefeet 120 can be mounted to the arm segments by using any known means,including welding, soldering, an adhesive, by a mechanical interferencefit, by a ball and socket arrangement, using locking geometries, using athumb or Allen screw friction locking mechanism, and/or a twist typelocking mechanism.

The feet 120 may be formed from a metal material, such as a superelasticmaterial, and have the polymer-based contacting surface (125)over-molded directly onto the feet, or be molded and then bonded to thefeet by a mechanical interference fit, an adhesive combination, or otherconventional attachment means as is well-known in the art.

Referring to FIGS. 31A-S, the contacting surfaces 125 can have a varietyof surface textures that are configured to resist slipping when placedagainst a tissue surface.

Referring to FIGS. 32A-H, the feet 120 themselves also can be formed tohave any geometry suitable or desired for the intended application. Asillustrated, the feet can be connected at one end, although such aconnection is not necessary in all applications. Some of the possiblegeometries include two parallel lines, “U”, “V”, “W”, and anycombination of these. The feet may be solid or have one or more lumensfor static or active suction, as described in more detail below. Thelumens may exit on the bottom of the feet 120, contacting surface 125,or any other suitable location. The bottom of the feet may be texturedto prevent slippage while in contact with the heart surface and in thismanner the need for the contacting surface 125 is lessened.

The formation or fabrication of the feet 120 and the contacting surface125 may be related. The contacting surface 125 may be partially orcompletely fabricated from many different types of syntheticbiocompatible materials, including expanded polytetrafluoroethylene(ePTFE), polyester (including PET), woven Dacron, PEEK, polypropylene,polyurethane, silicone, polyamide, polyimide, nylon, polyethylene,combination or other suitable materials. Some polymer materials could beirradiated in a desired geometry, for the shape to be “set” into thatposition, which could be helpful to provide a particular profile. Asimilar process using heat instead of radiation could be used where thethermoplastic polymer is annealed (and cooled) into a particular shapeand geometry.

The contacting surface 125 may be fabricated using injection-molding,casting, or other suitable molding techniques. The molds would bedesigned to mold the element/device material inside, outside,in-between, around, or any combination of these, the superelastic/shapememory (or other material) elements, making the elements an integralpart of the device. In general, the steps are as follows: an injectionmold is prepared, having the general characteristics that will result ina device shown herein. The superelastic/shape memory (or other)elements, such as the feet 120, are placed at desired locations in themold. The desired polymeric (or other) material is then injected intothe mold with the elements in place, prevented from moving, so that theyare integrated into the mold. The injected material is allowed to cure,and the contacting surface, with the elements (i.e., feet 120) areremoved from the mold. The superelastic/shape memory (or other) could beprocessed into the desired shape and configuration using severalmethods, such as electron discharge machining (EDM), laser cutting,chemical etching, grinding, cutting, photolithography, water jetcutting, any combination of these, or other suitable method.

As may be evident, the feet 120 and the contacting surfaces may havemany configurations. For example, the feet and/or contacting surfacesmay be in contact with the tissue using compression, suction (static oractive), cryo, adhesive (e.g., low strength or reversible bioadhesives),low durometer polymers, tissue penetration, protrusions, a combinationof these, or any other suitable method. There may be one or more feetand/or contacting surfaces. The feet and/or contacting surfaces may beseparate pieces; may be coated or bare; and/or may be made from a tube,rod, bar, coil, band, sheet, rectangular material, or other suitable rawstock. As illustrated above, the feet and/or contacting surfaces mayhave a profile that is elongated, rectangular, round, oval, trapezoidal,zigzag, combination of these, or another profile. The contactingsurfaces may have matching or mirrored geometries. The feet and/orcontacting surfaces may have holes, grooves, slots, or other openingsformed partially or completely through the width and or thickness. Thefeet and/or contacting surfaces may have the bottom, tissue contactingsurfaces, be textured, grooved, dimpled, a combination of these, orother surface, to prevent slippage while in contact with the heart. Thebottom of the feet and/or contacting surfaces may be concave, convex, ora combination of these configurations.

In addition to making the transition region between the shaft andfootpads essentially flat during insertion into the chest wall, thefootpads could also be folded together to reduce the cross sectionprofile. The feet and/or contacting surfaces may be fabricated withmetallic supports on the outside, the inside, in-between, or anycombination of these, to modify the rigidity, flexibility, or othercharacteristic of the feet and/or contacting surfaces. Moreover, theshape of the feet can be modified by inserting a reinforcing member intoan opening on the back end of the feet. The reinforcing member can beconfigured as described above and can be used to straighten, reinforce,or shape the feet. The reinforcing member or members can be malleable orrigid, or have a combination of these characteristics on the samemember, depending on the purpose or application for using it.

The feet and/or contacting surfaces may be constructed of one or moredurometer polymers. For example, the top (non-tissue contacting surface)may be made from a harder, higher durometer material than thetissue-contacting surface for increased rigidity, while not sacrificingtissue-contacting stability.

The feet and/or contacting surfaces may contain malleable materials onthe outside, the inside, in-between, or any combination of these thatwould allow regions or sections to be bent into custom geometries by thesurgeon. Alternatively, the feet and/or contacting surfaces may bereinforced with materials exhibiting spring-like characteristics. Thefeet and/or contacting surfaces may be designed and sold to beinterchangeable for different designs/purposes by the surgeon. The feetand/or contacting surfaces may have a consistent or variable thicknesscross-section for different purposes. For example, any area of thefootpad that would cross the artery (e.g., the bottom section of a “U”shape stabilizing segment) and possibly compress the vessel and restrictblood flow may be configured with a raised, concave section. The feetand/or contacting surfaces may have a geometry or other means to betterpresent (i.e., appose, bring together, or pucker) to the surgeon thecoronary vessel at the site of the anastomosis or the other targettissue to the surgeon.

The feet and/or contacting surfaces may be partially or completely madefrom very low durometer materials to assist or ensure better contactwith the tissue surface.

Referring to FIGS. 33A-35B, the stabilizer segment 110 or thecombination of the feet 120 and the contacting surface 125 can beconfigured with a suction apparatus 500 to apply suction to the tissuesurface to which the stabilizer is applied. A suction tube 505 can passthrough any one of, all or, or any combination of, the handle segment105, the arm segment 115, and the stabilizer segment 110. The suctiontube 505 also may be attached to the outside of the stabilizer andconnected to an opening in the contacting surface to the suctionapparatus 500. Such a suction tube 505 may be formed from a polymer witha metallic or polymer coil, braid, or winding on the inside, outside, orin-between two polymer layers to resist tubular collapse while thesuction is active. This configuration would also allow bending movementand/or positioning, while resisting kinking. As illustrated in FIGS.33A-35B, the suction apparatus 500 may be positioned at the bottom ofthe contacting surface 125 and may have suction spheres 510 throughwhich a vacuum is applied to the tissue. The suction apparatus also mayhave a screen mesh (not shown) or other screening system to preventtissue or other debris from clogging the suction tube 505. The suctionapparatus 500 also may include one or more rigid supports 515 that arepositioned within the suction apparatus and prevent it from collapsingupon itself when vacuum is applied to the suction apparatus. The rigidsupports 515 may include grooves, channels, or domes 520 that keep thevacuum flowing through the suction apparatus even when the sac-likeapparatus collapses upon itself.

Local suction can be accomplished by using soft, low durometer materialfor the suction spheres 510 on the tissue contacting surfaces, or byhaving lumens connecting the spheres 510 leading to a valve or fitting,such as a Luer fitting, to which a syringe, bulb, or other suctiondevice could be attached and a vacuum created, and the valve closed tomaintain the suction. In general, local suction is accomplished withoutattachment to an external vacuum source and instead is accomplished, forexample, using a syringe or other physician manipulated device to pull avacuum. A Luer-lock or stopcock then can be used to close the linecontaining the vacuum to leave a vacuum condition. In general, a remotevacuum suction system is attached to a vacuum line. To preventcollapsing of the vacuum line, a metallic or plastic coil may be usedinside of the line, in the wall of the line, or on the outside of theline.

Referring to FIG. 36, the stabilizer segment 110, the feet 120, and/orthe contact surface 125 may have a protrusion or barb 530 that isinserted into the tissue to be stabilized to prevent slippage of thestabilizer relative to the tissue. The protrusion or barb 530 may be inthe form of one or more wires 535 that pass through one or more lumens540 in the stabilizer from the proximal end, through the arm segment,and through any portion of the stabilizer segment. The wires 535 may becontrollably inserted to be limited in the depth to which they can beinserted. The control may be a stop on the proximal end of the wiresthat limits insertion of the wires into the lumens. Alternatively,protrusion may be molded or adhesively attached to tissue contactingareas. The protrusions may be straight or angled to prevent slippage inone or more planes.

Referring to FIGS. 37-41, a stabilizer 550 includes a handle 555, an arm560, and a stabilizer segment 565. The handle 555 includes a port 567for applying a vacuum to the stabilizer 550 and thumb switch 569 forcontrolling a linkage 570 within the arm 560 that is used to fix theposition of the stabilizer segment 565 relative to the arm 560. Thelinkage 570 may be as simple as a rod that slides within a channel inthe arm 560 and is connected to the stabilizer segment 565. The arm 560includes a first end 571 that is connected to the handle 555 and asecond end 573 that is adjacent to the stabilizer segment 565. Alsowithin the arm 560 is a vacuum tube or tubes 575 that pass between theport 567 and stabilizer segment 565. The linkage 570 terminates at thestabilizer segment 565 and includes an enlarged portion 577 that fitsagainst a curved surface 579. The enlarged portion 577 has a fixedposition relative to the arm 560. As such, retracting the thumb switch569 pulls the enlarged portion 577 in the direction of the curvedsurface 579 such that the enlarged portion and the curved surface are incontact to form a frictional fit. This friction fit prevents movement ofthe stabilizer segment 565 relative to the arm 560, a characteristicwhose importance will be explained in greater detail below.

Although the linkage 570 is described above as being a rod, the linkagemay be a wire or a cable that is positioned on the inside and or outsideof the arm 560 and connected to the thumb switch. As a result, when thethumb switch 569 is pulled backward, the distal end or end component ofthe arm 560 is in tension against a component or components attached tothe stabilizer segment 565. The thumb switch 569 also may be attached toan indexed movement (like a ratchet) or internal components thatincrease friction as they are moved in one direction.

The linkage 570 also may be implemented as a shaft, rod, or band oneither the inside or outside of stabilizer arm 560 and connected to thethumb switch 569. As a result, when the thumb switch is advancedforward, the distal end or end component of the arm is in compressionagainst a component or components attached to the stabilizer segment565. As in the implementation above, the thumb switch 569 may beattached to an indexed movement (like a ratchet) or internal componentsthat increase friction as they are moved in one direction.

The stabilizer segment 565 includes a pair of feet 581 that are joinedat the termination of the linkage 570. The feet 581 include ports 583for the vacuum lines 575 and tissue contacting segments 585 that includeopenings 587. The tissue contacting segments 585 can be separate piecesthat are mounted to the feet 581 by, for example, a frictional slidingfit. The segments 585 can be disposable to facilitate cleaning of thestabilizer. The segments 585 also can be fabricated from an atraumaticmaterial to reduce trauma to the tissue. The vacuum applied to the port567 passes through the vacuum lines 575 and applies a vacuum to theopenings 587. Thus, if the openings 587 are placed against tissue, suchas the heart, the vacuum will tend to pull the heart tissue against theopenings and position the stabilizer 550 against the heart muscle.

The stabilizer 550 can be fabricated from superelastic materials orshape memory materials depending on the characteristics that the surgeondesires from the stabilizer. For example, the arm 560 can be fabricatedfrom a superelastic material such that the arm bows without permanentdeformation. The superelastic resilience of the arm can be tailored suchthat the arm will bow if too much force is applied. This will limit thelikelihood that too much force will be exerted against the heart. Theelasticity of the arm also can be tailored such that applying forceagainst the arm to bow it will cause a magnified force to be presentedto the body applying the force. In general, the more the arm is bowedaway from its annealed or resting configuration, the more compressiveforce is exerted by the arm against the tissue. In this manner, thestabilizer can be fabricated apply a great force to the body. Thestabilizer segment 565 also benefits from the application ofsuperelastic materials. For example, the entire stabilizer segment 565or merely portions of it can be fabricated from a superelastic materialto provide the characteristics attained when superelastic materials areapplied to the arm 560.

The stabilizer 550 also can be fabricated from a shape memory metal sothat the stabilizer can be inserted into body cavity in a first, reducedprofile shape and then formed into a second shape. For example, thesecond shape can be formed as a result of exposure to body temperatureor by actively heating the stabilizer. The shape memory stabilizer thencan be withdrawn by cooling the stabilizer such that it returns to itsreduced profile shape for easy withdrawal or by simply withdrawing thedevice.

Referring to FIGS. 42-44, a stabilizer 600 is similar to the stabilizer550 except for differences in the stabilizer segment 601 and the linkage570. In particular, the enlarged portion 602 is larger than the enlargedportion 579 such that it will mate with an enlarged curved surface 604that is larger than the curved surface 579. When the thumb switch 569 isadvanced or retracted, depending upon the configuration as describedabove, the enlarged portion 602 mates with the curved surface 604 in africtional mating that limits the movement of the stabilizer segment 601with respect to the arm 560. Another difference between the stabilizer600 and the stabilizer 550 is the placement of the vacuum lines 575.Instead of running outside of the arm 560 at the distal end 573, thevacuum lines 575 are contained within the arm 560 and pass from the armto the stabilizer segment 601 without running on the outside of thestabilizer. To accomplish this, the vacuum lines 575 pass through thelinkage 570 at least at the enlarged portion 602. For example, if thelinkage 570 is in the form of a hollow tube, shaft, or rod, the vacuumlines 575 can be fed through the lumen of the tube, shaft, or rod. Thisadvantageously reduces the profile of the stabilizer 600 at the junctionbetween the arm 560 and the stabilizer segment 601. The stabilizersegment 601 has two sections, a tissue contacting section 606 and apivot section 608. The pivot section 608 is connected to the linkage 570and may include the enlarged portion 602. The tissue contacting section606 includes openings 610 through which vacuum is applied to fix thestabilizer 600 against a tissue surface, such as a surface of the heart.A channel 612 within the stabilizer segment 601 connects the vacuumlines 575 to the openings 610. The tissue contacting section 608 can bea replaceable part that snaps or slides into the pivot section 608.Alternatively, the tissue contacting section 608 can be integrallyformed or removable for cleaning.

Similarly to the stabilizer 550, the stabilizer segment 601 can befabricated in part or in whole from superelastic or shape memorymaterials to obtain the same objectives described above. For example,the pivot segment 608 can be formed from a superelastic material toprovide flexibility when the stabilizer is compressed against a tissuesurface. The tissue contacting section 606 also can be fabricated from asuperelastic material to provide flexibility.

Referring to FIGS. 45 and 46, a stabilizer 620 is configured to includean enlarged portion 623 and a large curved surface 625. However, unlikethe stabilizers 550 and 600, the stabilizer 620 is not configured toapply vacuum to a tissue surface. Instead, stabilization of the tissueis based on compression of the stabilizer segment 627 against the tissuesurface. To provide increased stability, the stabilizer segment 627 canhave a material applied to the tissue contacting surfaces 629 of thetissue contacting segments 631. The material has a non-slip surface sothat it will have a reduced tendency to slide across the surface of thetissue.

The arm 560 and the stabilizer segment 627 pivotally connected by theenlarged portion 623 and the curved surface 625 such that the arm andstabilizer segment can pivot with respect to each other. In addition,the enlarged portion 623 is connected to a sleeve 633 that encircles ashaft 635 such that the arm can rotate around the stabilizer segment.Thus there are two mechanisms to position the arm relative to thestabilizer segment. The shaft 635 is connected to the tissue contactingsegments 631 by a curved segment 636 that can be used to provide flexionin the stabilizer segment.

The tissue contacting segments 631 are marked with a guide 637 that isused by the surgeon to determine distances on the tissue surface. Forexample, the guide 637 can be marked in millimeter increments or Englishunit increments (e.g., sixteenths of an inch increments, eighth of aninch increments, etc.). This advantageously permits the surgeon to makethe arteriotomy the correct length by viewing the markings and usingthem as a reference.

The stabilizer 620 can be fabricated in part or in whole fromsuperelastic or shape memory materials. For example, the arm 560 can befabricated from a superelastic material and provide the advantagesdescribed above. Similarly, the stabilizer segment can be fabricated inpart or in whole from superelastic materials. For example, the curvedsegment 636 can be fabricated from a superelastic material to provideflexion in the stabilizer segment when the physician compresses thestabilizer against a tissue surface. The section of the linkage betweenthe enlarged portion 623 and the sleeve 633 also can be fabricated froma superelastic material to provide flexibility along that axis.

Referring also to FIG. 47, the stabilizer 620 can include a pivotconnection 642 between the arm 560 and the stabilizer segment 627 thatis reduced in size in comparison to the connection of FIGS. 45 and 46.This limits the range of pivot motion that is possible, which can beadvantageous in some circumstances in which there is little control ofthe stabilizer, such as in a confined space, and the physician wants tolimit the uncontrolled movement of the stabilizer segment.

Referring to FIGS. 48-51, a stabilizer 650 includes a pair ofindependent stabilizers 653 and a delivery tube 655 through which thestabilizers 653 independently are slidable. Each stabilizer includes ahandle 657, a shaft 659, and a foot 661. The handle 657 includes a port663 through which a vacuum can be applied. The shaft 659 includes alumen that connects to the foot 661 so that the vacuum can be appliedthrough openings 663 in the foot. The surgeon using the stabilizer 650can advance, rotate, and otherwise manipulate the independentstabilizers 653 to place them on a tissue surface adjacent to a surfaceto be operated upon.

The surgeon can insert the stabilizer 650 into a narrow opening by firstpulling the independent stabilizers 653 back such that the feet 661 arecompletely withdrawn into the delivery tube 655 to provide a reducedprofile (FIG. 51). With the delivery tube positioned within the bodycavity, the surgeon then advances the independent stabilizers 653,separately or together, until the feet 661 are extended. The surgeon canindependently manipulate the handles 657 to select a position of thefeet 661 that allows the surgeon to stabilize the tissue. Although FIGS.48-51 show simplified implementations of the feet 661, the feet can beimplemented in a more complex configuration with the curves and bendsillustrated in the feet and stabilizer segments described herein.

The center-to-center distance between the feet can be manipulated bymoving the feet 661 apart, creating a “V” shape. Additionally, a snap onspacer component may be positioned in between the two feet as describeabove with respect to FIGS. 26 and 27. Also, a thumb wheel type device(e.g., similar to that on a drafter's compass) may be used to manipulatethe center-to-center width of the feet.

The surgeon has the option of applying vacuum to stabilize tissue withthe stabilizer 650. The surgeon also can use the port and lumen toinstead provide a solution to the tissue that the stabilizer iscontacting. For example, the solution can be a therapeutic cooling orheating solution. The solution also can be a drug or other therapeuticagent. If the stabilizer is fabricated from a shape memory metal, thesurgeon can pass a heating solution through the port 663 and lumen tocause the shape of the independent stabilizers to reach their largerprofile shape. Then, when the stabilizer is to be removed, the surgeoninjects a cold solution to cause the shape to return to the reducedprofile configuration that is easily retracted into the tube 655. Ofcourse, the independent stabilizers, in whole or in part, can be madefrom a superelastic material such that the surgeon merely pulls theindependent stabilizers back into the tube 655 to cause them to be inthe reduced profile configuration.

Referring to FIGS. 52-54, a stabilizer 675 includes a handle 677, ashaft 679, and a stabilizer section 681. The shaft 679 is slidablewithin a delivery tube 683. The handle includes a port 685 for applyinga vacuum or delivery a fluid through a lumen in the shaft 679 to apply avacuum or deliver a fluid at the stabilizer section 681. The stabilizersection 681 includes openings 687 through which the vacuum or fluid isapplied to a tissue surface. The stabilizer section 681 also includes anopening 689 between opposite feet sections 691. The physician is able toperform a procedure on tissue through the opening 689. The opening isformed by cutting a round, oval, flat, or otherwise shaped shaft alongits length, generally along its central longitudinal axis. The cut canbe formed using any known conventional cutting method, including alaser, a cutting saw, chemical etching, electron discharge machining(EDM), stamping, photolithographic techniques, water jet, and/or anycombination of these methods or other suitable methods. The opposingsides of the cut then are forced outwardly to form the opening 689. Thecut can be made through a distal end 693 of the shaft or can stop shortof the distal end, as illustrated in FIGS. 52-54. The stabilizer 675then is formed by shaping (e.g., annealing) the shaft and attaching thehandle 677. Optionally, the distal end 693 can be elevated to preventocclusion of a coronary artery if the stabilizer 675 is to be used incoronary artery bypass procedures. The cutting operation results in twoconcave opposing halves of the tube. To enclose these open halves, theentire length of each cut tube is overmolded. Alternatively, portions(e.g., the top, side, and bottom) of each concave opening is overmoldedwith a polymer as described herein. This overmold creates channels(e.g., vacuum channels or fluid flow channels), functions as anatraumatic tissue contacting surface, and forms mating surfaces when thestabilizer is collapsed. In a derivative implementation, multipleincisions may be made along the length of the shaft. For example, onecentral incision may be made along the length and extend through thedistal end 693 and two incisions may be made in the thus formed opposingsegments of the shaft, although not completely through their distalends. Those two incisions then may be forced apart to form a pair ofstabilizing segments, each of which being similar to the stabilizingsegment illustrated in FIGS. 52-54.

The surgeon has the option of applying vacuum to adhere the tissue tothe stabilizer 675. The surgeon also can use the port 685 and lumen toinstead provide a solution to the tissue that the stabilizer iscontacting. For example, the solution can be a therapeutic cooling orheating solution. The solution also can be a drug or other therapeuticagent. If the stabilizer is fabricated from a shape memory metal, thesurgeon can pass a heating solution through the port 685 and lumen tocause the shape of the stabilizer (i.e., stabilizer segment 681) toreach its larger profile shape (FIG. 52). Then, when the stabilizer isto be removed from the body cavity, the surgeon injects a cold solutionto cause the shape to return to the reduced profile configuration thatis easily retracted into the tube 683 (FIG. 54). Of course, thestabilizer 675, in whole or in part, can be made from a superelasticmaterial such that the surgeon merely pulls the handle to pull thestabilizer segment 681 back into the tube 683 to cause it to be in thereduced profile configuration in which the opening 689 is closed.

Referring to FIGS. 55-58, a stabilizer 700 can be configured to have anyof the characteristics described above, such as vacuum application,fabricated from shape memory or superelastic materials, and/or withindex markings. However, rather than having an enlarged portion and acurved surface to form a pivotable linkage between the arm or shaft andthe stabilizer section, the stabilizer 700 includes a pivot mechanism705 formed by the interaction of a first ridged surface 710 and a secondridged surface 715. The first ridged surface 705 is formed in a shaft720 of the stabilizer segment 725. The second ridged surface 715 isformed in a lower clamp half 730 of a clamp mechanism 735 formed betweenthe lower clamp half 730 and an upper clamp half 740. The lower clamphalf 730 includes one or more wires, bands, or rods 743 that passthrough the stabilizer to a handle 745. Applying force to the handlelever 750 pulls the wires 743 in the direction of the handle 745, whichpulls the lower clamp half 730 in the direction of the upper clamp half740. The ridged surfaces 710 and 715 then mate to fix the position ofthe stabilizer segment 725 relative to the stabilizer 700. A ratchetmechanism can be used in the handle to maintain the fixation of theclamp halves 730 and 740 until the procedure is completed. It isbelieved that the pivot mechanism 705 can be applied to any of thestabilizers described herein by one of ordinary skill in the art.

Referring to FIGS. 59-61, an alternative pivot mechanism 775 includes afirst notched or ridged surface 777 and a second notched or ridgedsurface 779. The second notched or ridged surface 779 can be formed onone or more fins 781 formed on a pivot member 783. The notches or ridgeson the surface 777 interact in a mating fashion with the notches orridges in the surface 779. The fins 781 advantageously provide moreflexibility than, for example, a ball and socket joint, such that thefins and surface 777 will interact to form a stronger fixation of thestabilizer segment and the stabilizer. The surfaces 779 can be randomlyridged or notched (FIG. 59) or have multiple vertical spikes 783 thatfit into multiple vertical channels in the surface 777. Moreover,although four fins 781 are illustrated, fewer fins can be used or morefins can be used to provide satisfactory results.

Other methods of attaching the arm or shaft to the feet or stabilizersegment include an adjustable mechanism (e.g., macro and fineadjustment, vertical and horizontal adjustment), lockable mechanism,sliding mechanism, telescoping mechanism, and a side or top attachment.The feet or stabilizer segment can be attached to the side, top, orbottom of the arm, although only an attachment to the bottom of the armis illustrated indepth herein.

Of course, the stabilizer can be part of a multi-component system thatincludes a custom or commercially available retractor and arm or railsystem. Moreover, additional devices incorporating the technologydescribed herein may be inserted through the chest cavity or additionalmedical devices can be used with the stabilizer. For example, onedevice, such as the stabilizer, may be inserted through one site, andanother at a second site. Another device may be a heart retractor tosupport the heart, and/or section of the heart or other organ or tissue,during a cardiovascular surgical procedure, or other surgical ornon-surgical procedure. The heart-positioning device advantageouslysupports the heart during a coronary artery bypass surgery in a mannerthat will not damage the heart, but yet will allow easy access to thesurgical site without requiring the heart to be stopped and, moreover,while not unnecessarily constraining the heart. The heart positioner mayalso be used during conventional cardiopulmonary bypass supportedprocedures.

Moreover, as described in some detail above, the stabilizer, the heartposition, retractors, or other surgical tools described herein can beused to heat or cool tissue in a therapeutic or injury-preventativemanner that is separate from their intended use of stabilizing orretracting tissue. As described below, the stabilizer can includechannels through which a circulating fluid is passed. Although thedescription below is directed to a stabilizer implementation, othersurgical devices can be implemented using the technology and principlesdescribed herein. In one implementation, the stabilizer includes anelongated body through which a cooling fluid circulates to a tip portionthat is adapted to contact tissue and cool or heat that tissue. Thestabilizer may include a heat exchange region that is formed on anelongate shaft. The thermally transmissive core of the elongate shaftmay comprise one or more fluid circulation paths or lumens such thatheated or cooled fluid is passed into and/or extracted from the heatexchange region via the portion of the elongate shaft that is proximalto the heat exchange region. If the thermally transmissive core includesmultiple fluid flow lumens, a heat exchange fluid may be circulated intoor through the heat exchange region via such lumens.

Another method that can be used is a cryogenic method that includesproviding a phase change coolant that is pumped as a liquid to the tipof the stabilizer and undergoes its phase change in a small chamberlocated at the tip, for example on the tip of the stabilizer segment.The wall of the chamber contacts adjacent tissue directly to provide thecooling or ablation treatment. Such a stabilizer can treat or achieve arelatively high rate of heat energy transfer. By employing a phasechange refrigerant that can be injected at ambient temperature along thebody of the stabilizer and undergo expansion at the tip, the coolingeffect may be restricted to the localized treatment region surroundingthe tip portion of the stabilizer. The dimensions of stabilizerconstruction require that the phase change coolant be released from anozzle or tube opening at a relatively high pressure, into a relativelysmall distal chamber of the stabilizer. After the fluid expands in thedistal chamber and cools the walls, it is returned through the body ofthe stabilizer to a coolant collection system, preferably in the form ofa recirculation loop by, for example, a pump.

The cryogenic fluid can be provided in a liquid or a gas state. Anextremely low temperature can be achieved within the stabilizer, andmore particularly on the surface of the stabilizer, by cooling the fluidto a predetermined temperature prior to its introduction into thestabilizer, by allowing a liquid state cryogenic fluid to boil orvaporize, or by allowing a gas state cryogenic fluid to expand. Someliquids that can be used for this cooling include chlorodifluoromethane,polydimethylsiloxane, ethyl alcohol, and HFC's such as AZ-20 (a 50-50mixture of difluoromethane and pentafluoroethane sold by Allied Signal).Some gasses that can be used for this type of cooling include nitrousoxide and carbon dioxide

The cooling element of the stabilizer can include a means for coolingwith liquid nitrogen or a Peltier cell. A temperature sensor, such as athermocouple, is used to sense the surrounding temperature, for example,of the tissue and/or the device components. A controller is connected tothe sensor and receives the sensed temperature from the temperaturesensor and is configured to control the amount of power that is suppliedto the thermal element and change the temperature of a probe tip or tochange the temperature of the contacted tissue.

Similarly, the stabilizers and retractors described herein can be usedas a cryoprobe, cryosurgical ablation device, and/or cryostat andcryocooler for cryosurgery as a separate procedure or as an adjunct totissue stabilization. The stabilizer can use Joule-Thomson cooling inthe same manner as Joule-Thomson cryostats. These devices take advantageof the characteristic that most gases when rapidly expanded becomeextremely cold. In these devices, a high pressure gas such as argon ornitrogen is expanded through a nozzle inside a small cylindrical sheath,made of a metal or ceramic, and the Joule-Thomson expansion cools thesheath to sub-freezing cryogenic temperature very rapidly, which istransferred to surrounding tissue. One example of this type of device,although not a stabilizer, is illustrated in Sollami, U.S. Pat. No.3,800,552, which shows a basic Joule-Thomson probe with a sheath made ofmetal, a fin-tube helical gas supply line leading into a Joule Thomsonnozzle which directs expanding gas into the probe. Expanded gas isexhausted over the fin-tube helical gas supply line, and pre-coolsincoming high pressure gas. The coiled supply line is referred to as aheat exchanger and is beneficial because as it pre-cools incoming gas,it allows the probe to obtain lower temperatures.

In another implementation, the stabilizer can use the general conceptsof Joule-Thomson devices to be configured as a device that is used firstto freeze tissue and then to thaw the tissue with a heating cycle. Inthis implementation, nitrogen is supplied to a Joule-Thomson nozzle forthe cooling cycle, and helium is supplied to the same Joule-Thomsonnozzle for the warming cycle. The surfaces of the stabilizer to whichthe heating and cooling occur can be in contact with tissue to provide atherapeutic effect.

In another implementation, the stabilizer can be implemented as acryocooler for mass flow warming, with flushing backwards through thestabilizer, to warm the stabilizer after a cooling cycle. In thisimplementation, the stabilizer includes a supply line for high pressuregas to flow to a Joule-Thomson expansion nozzle and a second supply linefor the same gas to be supplied without passing through a Joule-Thomsonnozzle, thus warming the stabilizer with mass flow.

The stabilizer also can be implemented as a cryoprobe that uses afin-tube helical coil heat exchanger in a high pressure gas supply lineto a Joule-Thomson nozzle. The stabilizer would have a second inlet fora warming fluid, and would provide warming with mass flow of gassupplied at approximately 100 psi.

The stabilizer also can be implemented as a heat exchanger that includesa Giaque-Hampson heat exchanger with finned tube gas supply line coiledaround a mandrel. After expansion of the gas in the tip of thestabilizer, the gas next flows over the coils and exhausts out theproximal end of the stabilizer. The flow of the exhaust gas over theheat exchanger coils is controlled by placement of a flow-directingsheath that is placed in different longitudinal areas of the heatexchanger.

In another implementation of a tissue cooling stabilizer, retractor, orother surgical device, one or more parallel finned tubes can be used tocreate a dual helix design. In this implementation, two parallel gassupply lines are used, and are wound in parallel around a mandrel. Dualcoils also can be used to supply high pressure gas which cools uponexpansion (e.g., nitrogen, argon, NO₂, CO₂), so that both coils are usedfor cooling. One coil can be used for cooling gas while the other coilis used for the supply of a high pressure gas which heats upon expansion(hydrogen, helium, and neon).

In another implementation of a cooling and heating stabilizer, separatecooling and heating Joule-Thomson nozzles are used when the heating gasis supplied through a mandrel. In this implementation, the heating gassupply is not subject to heat exchange with the exhausting heating gasto create a higher initial heating rate. To permit complete control ofboth heating and cooling, such a cryostabilizer is supplied with gasthrough a dual manifold which allows for independently warming or eachportion of the stabilizer segment. If the stabilizer is a dual handlestabilizer with independent stabilizers (FIGS. 48 and 49) this allowsremoval of individual stabilizers in the event that the surgeon decidesthat a cryostabilizer must be moved. It also allows protective warmingfor nearby anatomical structures.

In another implementation of a cyrostabilizer, a medium flows in a firstlumen of the stabilizer, is pressurized, and is at a first temperaturejust distal of an expansion element. Upon passage through that expansionelement, the medium flows into a second lumen that is comparatively at alower pressure and temperature. This cooled medium is sufficient forcooling the tissue when the second lumen is appropriately placed inrelation to the tissue. The second lumen can include a bellows portionfor contacting the tissue and a cooling portion along the bellowsportion for cooling the tissue. The bellows portion is constructed tofacilitate contact between the cooling portion, or contact portion, ofthe cryostabilizer and the tissue. As such, the bellows portion may belongitudinally fixed, or longitudinally expandable or contractible.Moreover, at least the contact portion may be composed of a superelasticmetal alloy, such as nitinol, to provide desirable flexibility,strength, and longevity. Because of these desirable properties, theentire bellows portion may be composed of this material.

The expansion means of the cryostabilizer may be a media-flowrestriction device, such as an orifice sufficient for Joule-Thomsonexpansion of the medium flowing therethrough. The expansion means may belongitudinally moveable so that the tissue contacting portion can bemoved to a desirable longitudinal position along the bellows portion foroptimal cooling of the selected tissue.

The cryostabilizer may be advantageously employed over an operatingtemperature range of approximately normal body temperature to adesirable cooling temperature. For example, the cooling temperature atthe contact portion may be at less than or equal to approximately 0° C.to provide adhesion of the contact portion of the stabilizer to theselected tissue. The cooling temperature also may be as low asapproximately −10° C. to provide cold-mapping of cardiopulmonary tissue.This cooling temperature of the cryostabilizer may be lower, forexample, from approximately −20° C. to approximately −150° C., and moreparticularly, from about −70° C. to about −120° C., for forming anefficacious lesion in biological tissue.

The medium supplied in the cryostabilizer to the first lumen may bepre-cooled so that it is at a desirably low temperature before itreaches the expansion means for further cooling. Namely, a conduithaving a pre-cooling medium flowing therethrough may be positioned in anefficacious heat-exchange relationship with the first lumen of thecryostabilizer to pre-cool the medium flowing in the first lumen.Moreover, a second lumen of the cryostabilizer may be in an efficaciousheat-exchange relationship with the first lumen for further cooling ofthe medium flowing in the first lumen. With such heat-exchangerelationships, the cryostabilizer can achieve a very low coolingtemperature. Furthermore, the pre-cooling and cooling media may beselected to achieve, efficaciously, the cooling desired.

Referring to FIGS. 62-64, the principles described herein can be appliedto other surgical devices, such as a superelastic or shape memory tissueretractor 800. Such retractors can be used, for example, duringminimally invasive heart valve surgery or even other non-cardiovascularminimally invasive surgeries (e.g., laparoscopic, endoscopic,robotically assisted, and port access surgeries). The retractor 800includes a handle 805, an arm 810, a foot 815, and a delivery tube 820.The handle includes one or more ports 825 that are used, for example, tosupply vacuum or a fluid. The port 825 connects to one or more channels(not shown) that pass through the handle 805 and the arm 810 andterminate in the foot 815. The foot 815 includes an atraumatic surface830 and openings 835 that connect to one or both of a vacuum line and afluid line that are part of the channels connected to the ports 825. Assuch applying a vacuum to one of the ports will create a vacuum at theopenings 835.

The arm 810 and/or foot 815 can be fabricated from either a shape memorymaterial or a superelastic material. If a superelastic material is usedto fabricated either or both of the arm 810 and foot 815, the arm andfoot can be bent such that they can be inserted into the delivery tube820 for delivery through a narrow opening into a body cavity (FIG. 62).Then, the surgeon advances the handle 805 relative to the delivery tube820 to advance the foot 815 from the delivery tube. If made from asuperelastic material, the foot 815 will return to its unconstrainedshape (FIG. 64). The unconstrained shape can be that of an L or someother suitable shape for positioning, grasping, retracting, or otherwisemanipulating an organ, tissue, or vessel. The openings 835 arepositioned on the foot to be adjacent to the tissue in contact with thefoot 815 so that if vacuum is applied to the retractor 800, the vacuumwill further secure the tissue to the foot.

If the retractor 800 is made in whole or in part from a shape memorymaterial, the surgeon can use heating or cooling to change the shape ofthe retractor. For example, the surgeon places the arm 810 and foot 815in the delivery tube 820 with the arm and foot in a constrainedposition. Then, the surgeon advances the handle 805 to advance the foot815 out of the delivery tube 820. As shown in FIG. 63, because theretractor is made from a shape memory material, it will not immediatelyreturn to it unconstrained shape. Instead, by applying a heatingsolution through one of the ports 825, the heating solution will passthrough the handle 805, the arm 810, and into the foot 815 such that theshape of the foot 815 returns to its unconstrained position (FIG. 64).The channel through which the heating solution flows can be open toseparate openings 835 a or closed. If open to the openings 835 a, theheating solution will irrigate the surgical field at the same time thatit heats the shape memory material and causes the material to return toits unconstrained configuration. If the channels do not flow intoopenings, a heating solution can be repeatedly infused and withdrawnuntil the retractor returns to the unconstrained configuration. In oneimplementation, a dual lumen catheter is inserted into the port andpassed into the foot. One lumen of the catheter is used to inject theheating solution and the second lumen is used to withdraw the heatingsolution. When the retractor is to be removed, the surgeon can thenapply a cooling solution into the port 825 to cool the arm 810 and foot815. The cooled arm and foot then can be easily retracted into deliverytube 820 and the delivery tube and stabilizer withdrawn from the bodycavity. Alternatively, the surgeon can simply retract the handle 805 topull the foot back into the delivery tube relying on the resilience ofthe arm and foot to fit the foot into the tube.

As explained above, the retractor can include one or more channels. Oneor more of the channels can be used to infuse therapeutic orpreventative agents into the surgical field. The channels also can beused to deliver a catheter-based light fiber to illuminate the surgicalfield, a RF-device (e.g., for coagulating, cutting, and/or ablatingtissue), a gas to expand the body cavity surrounding the surgical field,and/or an instrument or catheter-based device to manipulate the surgicalfield. For example, a catheter-based biopsy device can be passed throughone of the channels to take a tissue biopsy. Moreover, the channels canbe used to receive rigidifying mandrils or shaping mandrils to shape theretractor. Although FIGS. 62-64 illustrate the application of vacuum,the devices can be configured as simply as superelastic tubes that passthrough delivery tubes or with any of the individual features describedabove.

Similarly to FIGS. 62-64, a surgical device or tool, such as aretractor, can be formed with other shapes that are useful in a widerange of surgical procedures. For example, referring to FIGS. 65 and 66,the instrument can have a J shape, or referring to FIGS. 67 and 68, theinstrument can have a hockey stick shape. As illustrated in FIGS. 65 and66, surgical device 850 includes a J-shaped instrument 853 that ispassed through a delivery tube 855 such that a J-shaped portion 860 ofthe instrument is delivered to a surgical site to move, reposition, ormanipulate tissue. The device 850 can be advanced in part or in wholefrom the delivery tube 855 such that the instrument 853 forms a curvedshape that varies between a slightly curved shape and a completeJ-shape.

Similarly, in FIGS. 67 and 68, a surgical device 865 includes a hockeystick shaped instrument 867 that has a hockey-stick shaped portion 870that can be advanced in whole or in part from the delivery tube 855 suchthat the instrument forms an angled member that varies with respect tothe delivery tube between collinear to any desired angle based on theangle imparted in the instrument 867 during fabrication.

The surgical devices 850 and 865 can be fabricated from the samematerials as the devices of FIGS. 62-64 and be used in the same mannerfor similar purposes (e.g., deliver heat, provide cooling, deliverinstruments, deliver therapeutic agents, etc.). Moreover, any or all ofthe features shown in the devices of FIGS. 62-64 can be implemented inthe device 850 and 865.

While several particular forms of the invention have been illustratedand described, it will be apparent that various modifications andcombinations of the invention detailed in the text and drawings can bemade without departing from the spirit and scope of the invention. Forexample, references to materials of construction, methods ofconstruction, specific dimensions, shapes, utilities or applications arealso not intended to be limiting in any manner and other materials anddimensions could be substituted and remain within the spirit and scopeof the invention. For example, the arm segment or shaft can beconfigured to provide more stable locking to the arm, retractor or railby knurling the shaft, providing a matching interlocking geometry to thearm, retractor or rail, etc. The stabilizing segment, feet, and/orcontacting surface may be dimpled or roughened to reduce slippageagainst the tissue. As illustrated in FIGS. 69-71, and with reference toFIGS. 62-64, the stabilizer also can be used as a carrier for atherapeutic or diagnostic device 890, such as an electrophysiologycatheter or other device for performing tissue ablation, such asexterior pulmonary vein ablation for treating atrial fibrillation. Whenused in this manner, the top and sides of the foot pads or feet canfunction as a thermal insulator to prevent secondary thermal damage tosurrounding or adjacent tissue. Because the stabilizer also functions tomaintain sufficient contact against tissue, the stabilizer thus can beused to carry a therapeutic or diagnostic device or catheter 890 to thetissue to perform a diagnostic or therapeutic procedure. Alternatively,a catheter or other device 890 can be passed through a lumen 891 in thestabilizer and/or into an opening, groove, slot, or hole 892 in thestabilizing segment, feet, and/or contacting surface to perform adiagnostic or therapeutic procedure on the tissue in which thestabilizer is in contact. The device can be used during conventionalsuturing of an artery in a coronary artery bypass grafting procedure, aswell as in the placement of sutureless anastomotic connectors.Accordingly, it is not intended that the invention be limited, except asby the appended claims.

1-20. (canceled)
 21. A method of provide a surgical instrument fortemporary use in a medical procedure in a mammalian body, the methodcomprising: providing a surgical instrument fabricated from asuperelastic material and being configured to be changed between atleast a first shape and a second shape upon application or removal of aforce, the surgical instrument comprising: a delivery device, a firstmember, a second member having a surface configured to contact tissue,and a means to apply a force to one or both of the first member and thesecond member to change the shape between the first shape and the secondshape; applying a force to one or both of the first member and thesecond member and placing one or both of the first member and the secondmember into the delivery device in the first shape; advancing thedelivery device in the mammalian body; advancing the first member andthe second member relative to the delivery device such that at least oneof the first member and the second member extend out of the deliverydevice into the mammalian body; removing the force from one or both ofthe first member and the second member to change the shape of one orboth of the first member and the second member from the first shape to asecond shape; and\ using the second member to contact tissue.
 22. Asurgical device configured to position a surgical instrument against atissue surface, the surgical device comprising: an arm including a lumenconfigured to receive the surgical instrument; and a foot extending fromthe arm, wherein the foot includes an atraumatic, tissue contactingsurface configured to be pressed against the tissue surface, one or moreopenings on or extending from the atraumatic tissue contacting surfaceand being configured to apply vacuum or a fluid to the tissue surface,and one or more of an opening, groove, slot or hole in the atraumatictissue contacting surface, the opening, groove, slot or hole configuredto accept the surgical instrument from the lumen in the arm and containthe surgical instrument, whereby the surgical instrument can be used toperform a diagnostic or therapeutic procedure on the tissue againstwhich the surgical device is in contact.
 23. The surgical device ofclaim 22, wherein the surgical instrument comprises one or more of anablation device, a radiofrequency device, a tissue cooling device, adiagnostic device, and a therapeutic device.
 24. A surgical deviceconfigured to position a surgical instrument against a tissue surface,the surgical device comprising: an arm including a lumen configured toreceive the surgical instrument; and a foot extending from the arm,wherein the foot includes an atraumatic, tissue contacting surfaceconfigured to be pressed against the tissue surface, the tissuecontacting surface comprising a pair of adjacent members, the pair ofadjacent members each having at least one surface being generallyperpendicular to the tissue contacting surface and forming a plane thatis opposed to a surface on the opposite adjacent member, the surfacesforming the opposed planes being of generally equal lengths andseparated from one another by a distance that is less than the length ofeach plane, one or more openings on or extending from the atraumatictissue contacting surface and being configured to apply vacuum or afluid to the tissue surface, and one or more of an opening, groove, slotor hole in the atraumatic tissue contacting surface, the opening,groove, slot or hole being formed between the adjacent members anddefined on two sides by the surfaces forming the opposed planes andbeing configured to accept the surgical instrument from the lumen in thearm and contain the surgical instrument, whereby the surgical instrumentcan be used to perform a diagnostic or therapeutic procedure on thetissue against which the surgical device is in contact.